The present invention relates to a self-adhesive temperature indicator--see e.g. U.S. Pat. No. 3,002,385.
Self-adhesive temperature indicators are known in which a layer of material (which changes color at a predetermined temperature) is provided on a piece of transparent or translucent foil. It is common to print a colored layer over an area of the foil, for various purposes. The usual arrangement is for the printed layer to be on the upper side of the foil and the indicating material and a layer of adhesive on the under-side. However, it is desirable to protect the printed layer, but if it is placed on the under-side, it will be disposed between the foil and the adhesive: it would, however, not be able to transmit the necessary mechanical forces and would disintegrate.